The act of breathing depends on coordinated activity of the respiratory muscles to generate sub-atmospheric pressure. This action is compromised by disease states affecting anatomical sites ranging from the cerebral cortex to the alveolar sac. Weakness of the respiratory muscles can dominate the clinical manifestations in the later stages of several primary neurologic and neuromuscular disorders in a manner unique to each disease state.
Structural abnormalities of the thoracic cage, such as scoliosis or flail chest, interfere with the action of the respiratory muscles again in a manner unique to each disease state. The hyperinflation that accompanies diseases of the airways interferes with the ability of the respiratory muscles to generate sub-atmospheric pressure and it increases the load on the respiratory muscles. Impaired respiratory muscle function is the most severe consequence of several newly described syndromes affecting critically ill patients. Research on the respiratory muscles embraces techniques of molecular biology, integrative physiology, and controlled clinical trials. A detailed understanding of disease states affecting the respiratory muscles is necessary for every physician who practices pulmonary medicine or critical care medicine.
Respiratory muscle function is monitored at a rudimentary level in routine critical care practice. Stagnation in diagnostic and monitoring techniques may have stemmed from the paucity of new therapies directed at the respiratory muscles. The mechanisms whereby cytokines cause respiratory muscle dysfunction are rapidly unfolding and new pharmacologic agents have been developed. Together, these advances should motivate the introduction of more advanced diagnostic and monitoring techniques into everyday clinical practice.
Disappointingly, the gap between basic understanding of pathophysiologic mechanisms and the translation of this knowledge into improvements in patient outcome has widened over the last 25 years. It is hoped that this gap will be narrowed by the time of the next State-of-the-Art review on respiratory muscles.
Managing acute pathology of often relies on the addressing underlying pathology and symptoms of the disease. There is currently a need in the art for new compositions to treatment of respiratory disorders.